merge(third_party/git): Merge squashed git subtree at v2.23.0

Merge commit '1b593e1ea4' as 'third_party/git'

third_party/git/t/t4062-diff-pickaxe.sh

@@ -0,0 +1,29 @@
+#!/bin/sh
+#
+# Copyright (c) 2016 Johannes Schindelin
+#
+
+test_description='Pickaxe options'
+
+. ./test-lib.sh
+
+test_expect_success setup '
+	test_commit initial &&
+	printf "%04096d" 0 >4096-zeroes.txt &&
+	git add 4096-zeroes.txt &&
+	test_tick &&
+	git commit -m "A 4k file"
+'
+
+# OpenBSD only supports up to 255 repetitions, so repeat twice for 64*64=4096.
+test_expect_success '-G matches' '
+	git diff --name-only -G "^(0{64}){64}$" HEAD^ >out &&
+	test 4096-zeroes.txt = "$(cat out)"
+'
+
+test_expect_success '-S --pickaxe-regex' '
+	git diff --name-only -S0 --pickaxe-regex HEAD^ >out &&
+	verbose test 4096-zeroes.txt = "$(cat out)"
+'
+
+test_done